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Discussion Starter #1
When I go to start my 02 vn750 I get a single click from under the seat, then lose all power. If I let it sit for a bit, I'll get power again, but if I hit the starter button, it does the same thing. Any suggestions?
 

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FREEBIRDS MC CENTRAL NY
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Dead battery?loose battery cables?
 

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Discussion Starter #4
The battery tests at 12.4 volts. I am leaning more towards the battery however because I have auxiliary lights and a radio wired direct to the battery and they don't work either
 

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FREEBIRDS MC CENTRAL NY
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The battery tests at 12.4 volts. I am leaning more towards the battery however because I have auxiliary lights and a radio wired direct to the battery and they don't work either
Should be at least 12.8
 

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Sparky!!!
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The battery tests at 12.4 volts. I am leaning more towards the battery however because I have auxiliary lights and a radio wired direct to the battery and they don't work either
This leads me to think bad grounds.. 12.4 Volts is plenty of voltage to run a radio, and 10 volts is all that is needed to light a light bulb dimly (unless we are talking HID or LED lights).
 

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So where is a good place to get a voltage reading away from the battery terminals? I remember seeing aux power cables on one of the wiring diagrams...
 

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Sparky!!!
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there are two sets of Accessory power leads.. one set is in the headlight bucket, and the other is on the right side of the battery box... but I don't like using either set for testing voltage.. the best place to test voltage is on the brown wire going into the dash panel.. as almost every system ties into that wire in some way or another.
 

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So where is a good place to get a voltage reading away from the battery terminals? I remember seeing aux power cables on one of the wiring diagrams...

As you are fully aware, i am only an idiot n00b and have absolutely no idea what i am talking about, but i *do* have the highest percentage of plain old dumb luck statically charged into my being from rubbing my pant legs up against so many car doors every day while lane splitting, so with that said, and with it given that my bike is an '87 California model . . .


Two places i can think of that should be checked and are pretty easy to check are the red terminals on each of the ignition coil primaries. The ignition coils have two little tabs on them that booted wires hook up to, and they have two spark plug cables running out of the the side. If those are low voltage then the fire in the spark plugs is going to be likewise lower, and that is true as a formula as long as the coils are good ( no shorts inside themselves between their windings ). The front cylinder's ignition coil is under the front left neck-shield over the left front ear ( remember that screw i was talking about that fell between the frame and the radiator? yeah, keep your fingers on those as they come out. :) ). And the rear's ignition coil is on the front side of the battery box. Both measurements are on the left side of the bike. You should also test with three different grounds ( or more ). For example, sticking the meter probe into the back of the connector's jacket for the positive side of either coil frees up one of your hands, but also keeps that connection "steady" as it can be. The rubber holds the probe in place ( presuming your connecting boots are like mine which as you know could be totally different even though nothing on this bike has ever changed over the years ;) ). In any case, after your probe is solid on one of the coils, use the other probe to first, the frame, then the crankcase itself, and then the battery negative terminal. These are the three major grounds on the bike ( battery box excluded ). Several parts rely on the frame to be ground ( for example, the fan switch has one wire feeding it ). And there is a big black wire from the crankcase to the battery box on the right side where the battery box bolts onto the frame. This is ( electrically speaking ) the "common ground" even though the Kawi electrical engineers in their infinite wisdom chose to run the negative battery terminal some place else ( disregarding every design principle ever penned and giving people like Slim good valid reasons to "lean toward the ground" ). Regardless of where you make those measurements for ground, your voltage to either coil should be the same. To clarify, if you, for example, have the red probe on the rear coil's red wire, you should see the same reading for voltage regardless of which of the three ( or more ) grounds you choose. If there is a difference beyond a tenth of a volt, then you have what is known as a "voltage drop" between those two points of ground. If there is NO voltage or a huge difference in your voltage at any two grounds, then you have a "broken connection" which simply means one of your grounds is no longer hooked up mechanically enough to pass electricity ( could be corrosion, loose, disconnected, have some kind of junk that found its way there by somebody's kludge like a rubber washer, etc. ). On paper, and ideally, the readings should be exactly the same. Another reading to check is that both of your coils should be the same voltage as well. So if you are reading, let's say, 13.2 volts on the front coil using one particular ground, that same ground point should result in you reading 13.2 volts on the rear coil as well. If they are different then you probably have a short, or a near short, or a leaky capacitive or resistive short in your harness or in, around, or near the connectors to your ignitor box. The ignitor box is that fairly large black square box with the square rubber hood surrounding its two molex connector sockets on the right rear lower side of the battery box. If either of your coil primaries are shorted, then you will also get a different voltage reading on that second test. It wouldn't necessarily mean that the coil was no longer useful, it would only mean that a section inside had lost its insulation between two or more windings. On the presumption that at least ONE of your coils is "good", you could test them in two different ways. 1) by swapping them one with the other 2) by measuring the resistance in each of them ( which should be approximately the same ).

Hope this helps, and please remember, i am only chiming in because the experts have yet to find the time, so for now, please accept some of my dumb luck advice.


:nerd:
 
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So where is a good place to get a voltage reading away from the battery terminals? I remember seeing aux power cables on one of the wiring diagrams...
The accessory wires in the headlight bucket or under the right side cover would work fine. But the best place to test voltage is across the battery terminals.
Testing with both the motor off and the motor running will show if you're getting a charge.

Not sure why you'd need to test the coils unless you suspected a problem with them.




(And look, I answered that without a 800 word paragraph;))

http://www.bobbrooke.com/WritersCorner/paragraphswhentouse.htm


;)
 

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FREEBIRDS MC CENTRAL NY
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The accessory wires in the headlight bucket or under the right side cover would work fine. But the best place to test voltage is across the battery terminals.
Testing with both the motor off and the motor running will show if you're getting a charge.

Not sure why you'd need to test the coils unless you suspected a problem with them.




(And look, I answered that without a 800 word paragraph;))
Wow KM,you can count too;)
 

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Thanks for the details,Slim and RoadHopper. Good to get a feel of how everything ties together. Its hard to physically trace the wires, since everything is bundled and shoved through little cracks and impossibly buried.
 

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The accessory wires in the headlight bucket or under the right side cover would work fine. But the best place to test voltage is across the battery terminals.
Testing with both the motor off and the motor running will show if you're getting a charge.

Not sure why you'd need to test the coils unless you suspected a problem with them.

(And look, I answered that without a 800 word paragraph;))


Paragraphs and When to Use Them


;)
See, there you go again, "not making friends fast". You should make up your goddamned mind.

P.S. if you don't get what i mean, too bad, this is the short version.
 

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See, there you go again, "not making friends fast". You should make up your goddamned mind.

P.S. if you don't get what i mean, too bad, this is the short version.
If you can't take some teasing or leg pulling, you're going to have a hard time here.
But on a serious note, do try and break up your long posts into paragraphs. Many here read from their phones and it can be difficult to follow lines of text without breaks in them.

Thanks!
 

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If you can't take some teasing or leg pulling, you're going to have a hard time here.
But on a serious note, do try and break up your long posts into paragraphs. Many here read from their phones and it can be difficult to follow lines of text without breaks in them.

Thanks!

I answered his question because i respect him not because i'm getting paid.

You're welcome.
 

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Its hard to physically trace the wires, since everything is bundled and shoved through little cracks and impossibly buried.
They wired this bike the way they did because it was cheaper in both parts and assembly time at the factory and would last "long enough" to keep the bike selling. Can't blame them for that, but at least for my bike, she'll be 30 years old next year.

Sometime next week i will be starting a project to rewire the entire bike. Part of that will include metal connector cables to a little box i plan on mounting near the horns with a circuit board inside. Not a big project for me, also not a small project for anyone including me, but i do intend on doxxing the entire project with design notes and photos of every last step.
 

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FREEBIRDS MC CENTRAL NY
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Mods don't get paid either
I don't remember twisting anyone's arm to read what i wrote, especially on a phone. Is he forced to read it because he's a mod or something?

I'll bet this tiny little box i typed it all into is smaller than his phone.

:grin2:
 

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I don't remember twisting anyone's arm to read what i wrote, especially on a phone. Is he forced to read it because he's a mod or something?

I'll bet this tiny little box i typed it all into is smaller than his phone.

:grin2:
I'm not forced to read anything. But I do try and read any information any member posts. I've been doing that for almost 12 years now.
You, not so long.

Writing posts and making them easy for ALL members here to read is just basic courtesy. If you in fact answered because you "respect him" perhaps you should show some respect to the rest of the members here too...I don't give a fuk what you think about me, but show some respect for the others on this site.
 

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I'm not forced to read anything. But I do try and read any information any member posts. I've been doing that for almost 12 years now.
You, not so long.

Writing posts and making them easy for ALL members here to read is just basic courtesy. If you in fact answered because you "respect him" perhaps you should show some respect to the rest of the members here too...I don't give a fuk what you think about me, but show some respect for the others on this site.
Make up your mind, you can't have it both ways. And if you've got an issue, take it to PM.

Thanks
 
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